Secondary heating device



Sept. 28, 1937. F. HAID SECONDARY HEATING DEVICE Filed Sept. 12, 1936 Frank Ha INVENTOR. BY Z ATTORNEY Patented Sept. 28, 1937 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to a secondary heating device for warm air heaters.

The principal object of this device is to provide a secondary heater introducing forced air into a coil positioned within the combustion chamber of a heating device, one end of the coil being brought out between the casing and the fire pot and combustion chamber.

A further object is to provide means for taking air from a cold air return pipe in a house installation of a furnace and, by means of a fan, forcing it through a coil positioned within a combustion chamber of a heating device, and bringing the heated air downwardly and forcing it in a circular and upward motion from a position near the bottom of a fire pot when expelled from the coil end.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that changes in the precise embodiment of the invention herein disclosed, can be made within the scope of what is claimed, without departing from the spirit of the invention.

The figure is a vertical side elevation of the device with parts broken away, and showing the installation of the device in an ordinary warm air furnace.

By referring to the drawing it will be seen that there is provided a furnace casing I having installed therein an ordinary fire pot 2. It will be 35 seen that there is provided an electric fan 3 connected to the cold air return 4. This electric fan 3 is connected to an intake tube 5 passing through the casing l at a point 6. This tube 5 then is projected through an opening of the combustion chamber 1 at a point 8.

It will be seen that a continuation of this tube 5, after passing through the combustion chamber wall at a point 8, is formed into a cone-shaped coil 5 0 having a lower portion l0 passing through the combustion chamber 7 at a point ll This lower portion i0 is provided with a curved lower end I 2 through which the hot air is expelled causing the air to be set in circulation around the outside of 10 the fire pot and finally finding its way up to the warm air pipes of the furnace.

What I claim is:--

1. In combination with a warm air furnace comprising a fire box and radiator unit and a 15 casing for the same having a cold air return, a secondary heating device comprising a tubular coil positioned within a combustion chamber of the furnace, a blower for taking air from a cold air return of the furnace and forcing the same into 20 said tubular coil, a lower end of said tubularcoil extending downwardly for the purpose of expelling heated air near the lower portion of the fire pot between the furnace casing and the fire pot.

2. In combination with a warm air furnace 25 comprising a fire box and radiator unit and a casing for the same having a cold air return, a secondary heating device comprising a tubular coil positioned within a combustion chamber of the furnace, an electric fan for taking air from a cold 30 air return pipe of the furnace and forcing the same into said tubular coil, a lower end of said tubular coil extending downwardly and having a curved end for the purpose of expelling heated air near the lower portion of the fire pot between the furnace casing and the fire pot, substantially as described.

FRANK HAID. 

